Not fully, but in practice to benefit from no trade barriers. And it'll be done by 2040.
I think what we'll get is no more singular head of state because the Unitary Executive model is a flawed premise that highlights the fragility of having only one person as the chief executive. It's a poison pill. Suggesting it is to suggest inevitable death of the Republic.
What we'll end up with our scaled up Switzerland. An Executive Council of 5/7/9 regionally elected members, with a rotation of who is the ceremonial head of state for functions. I like 7, with more of the East Coast and Midwest consolidated.
But whew...the constitution will need a major overhaul for that to work.